The present invention relates to a thermal compound composition having not only high thermal conductivity but also an electrical insulation property. The thermal compound has to possess high thermal conductivity so as to ensure a heat dissipation function, but electrical conductivity is typically increased therewith due to the component used to increase thermal conductivity, and thus the use thereof is difficult in devices requiring an electrical insulation property. The present invention relates to a technique for a thermal compound composition having high thermal conductivity and a good electrical insulation property.
Due to the high integration of electronic parts, a large amount of heat is generated upon operating the parts, thus applying an excessive load to products and also having a negative influence on the performance and lifetime of the products. With the goal of solving the problem of heat generation in electronic parts, many attempts are made to synthesize and apply a heat-dissipating material so as to enhance the performance of products. Such a heat-dissipating material is exemplified by a thermal compound (or thermal grease).
A thermal compound is adhesive and contains silicone oil as a main resin thereof, and maintaining stable adhesion even under severe conditions is regarded as important. A thermal compound is typically prepared by mixing a silicone base with inorganic particles having high thermal conductivity as a heat-dissipating filler. Examples of the heat-dissipating filler used therefor may include alumina, boron nitride, aluminum nitride, zinc oxide, and magnesium oxide, all of which have high thermal conductivity so as to dissipate heat effectively.
The related technical documents for existing thermal compounds or thermal grease are as follows.
Korean Patent No. 10-0603490 discloses a silicone grease composition for heat radiation, which is thermal silicone grease that may exhibit stable thermal conductivity for a long period of time and is highly reliable, whereby oil pollutants are not generated and contact defects do not occur, the composition comprising (A) 100 parts by weight of organopolysiloxane having thixotropy α of 1.03 to 1.50 and a viscosity of 100 to 1,000,000 mm2/s at 25° C., and (B) 100 to 2,000 parts by weight of a thermal conductive inorganic filler having an average particle size of 0.1 to 100 μm.
Also, Korean Patent No. 10-0786747 discloses a greasy silicone composition containing a large amount of a thickener and having high heat resistance, comprising (A) liquid organopolysiloxane composed of 80 to 96.5 mol % of a siloxane unit represented by the formula of R2SiO2/2, 1.0 to 10.0 mol % of a siloxane unit represented by the formula of RSiO3/2, and 0.25 to 10.0 mol % of a siloxane unit represented by the formula of R3SiO1/2 (wherein individual Rs, which are the same as or different from each other, are a monovalent hydrocarbon group) and (B) a thermal conductive powder.
Also, Korean Patent No. 10-1073164 discloses a heat-dissipating silicone grease composition having high thermal conductivity and high coatability, comprising (A) 3 to 30 mass % of organopolysiloxane having a kinematic viscosity of 50 to 500000 mm2/s at 25° C., (B) 60 to 96.9 mass % of a thermal conductive filler having a thermal conductivity of 10 W/(m·K) or more, and (C) 0.1 to 10 mass % of a solvent for dispersing or dissolving the (A) component.
Furthermore, Korean Patent Nos. 10-1155940 and 10-1336517, Korean Patent Application Publication No. 10-2010-0059684, Korean Patent No. 10-1498516, and Korean Patent Application Publication No. 10-2012-0035878 have also been disclosed.
These conventional related documents are mainly focused on improving the thermal conductivity of the thermal compound. However, electrical conductivity is also increased due to the component of the filler used for increasing thermal conductivity, and the use of such a thermal compound is limited to devices requiring electrical insulation properties due to problems related to short-circuits. Hence, the present invention has been devised to respond to the need for the development of a thermal compound having high thermal conductivity and a good electrical insulation property.